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## Subtract a one-digit number

**Linked from:** Number and Algebra: Whole number operations 95-104

**Content strand:** Number and Algebra

**PAT Maths descriptor:** Subtract a one-digit number from a two-digit number.

**Curriculum code:** ACMNA015

### Prerequisites

- Subtraction strategies
- Counting on or counting back for subtraction

### Key concepts and skills

- Identifying which operation to use in a word problem
- Subtracting a one-digit number from a two-digit number

### Question

### Common errors and misconceptions

Key |
19 |

Item commentary |
This item requires students to identify and link the relevant elements of the information provided; select and apply an appropriate strategy (subtraction); and communicate the result of a calculation as a single numeric result. |

A common error may be adding the two numbers in the question. | |

A common error may be making a subtraction error such as 24 – 5 = 20. | |

A difficulty may be reading the word 'five' and it is read as a different number. |

### Linked concept builders

- Subtraction of one-digit numbers
- Devising strategies
- Communication
- Identifying which operation to use in a word problem

### Moving forward

- Subtraction of ten (Concept builder)